LAUSR

The high-resolution mid-infrared spectrometer instrument will fly onboard the National Aeronautics and Space Administration’s airborne stratospheric observatory for infrared astronomy in 2019. It will provide astronomers with a unique observing window (25–122 $$\upmu \hbox {m}$$μm) for exploring the evolution of protoplanetary disks into young solar systems. There are two focal plane detector arrays for the instrument: a high-resolution ($$\lambda / {\varDelta }\lambda \,=\,100{,}000$$λ/Δλ=100,000) $$8\times 16$$8×16 detector array, with a target noise-equivalent power, $$\hbox {NEP} \le 3 \hbox { aW}/\sqrt{\mathrm{Hz}}$$NEP≤3aW/Hz, and a low-resolution ($$\lambda / {\varDelta }\lambda =600$$λ/Δλ=600–19,000) $$16\times 64$$16×64 detector array with a target $$\hbox {NEP }\le 20\hbox { aW}/\sqrt{\mathrm{Hz}}$$NEP≤20aW/Hz. The detectors for both of these arrays are superconducting Mo/Au bilayer transition-edge sensor bolometers on suspended single-crystal silicon membranes. We present detector characterization results for both arrays, including measurements of thermal conductance in comparison with phonon transport models, and measurements of saturation power and noise.